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Interpretation Response #13-0117 ([DuPont Company] [Mr. Randy Martin])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: DuPont Company

Individual Name: Mr. Randy Martin

Location State: DE Country: US

View the Interpretation Document

Response text:

July 25, 2013


Mr. Randy Martin
DuPont Company
Sourcing & Logistics
974 Centre Road
P.O. Box 2915
Wilmington, DE 19805

Ref No.: 13-0117

Dear Mr. Martin:

This is a response to your May 23, 2013 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) with regard to the loading requirements for portable tanks.  Specifically, you seek clarification on the loading of high viscosity liquids in portable tanks as specified in § 173.32(f)(5).  In your email, you request clarification of the applicability of filling restrictions for portable tanks found in § 173.32(f)(5), commonly referred to as the “80/20 Rule.”  Your questions are paraphrased and answered below.  

Q1:  Does § 173.32(f)(5) only apply to IM and UN portable tanks  and not DOT speciation 51 tanks?

A1: The answer is yes.  This subparagraph refers specifically to IM or UN portable tanks, and does not apply to DOT 51 portable tanks.  

Q2.  For what materials does the “80/20 Rule” apply to the filling of IM or UN portable tanks with?

A2.  These restrictions are applicable when filling an IM or UN portable tank with materials other than non-flowable solids and liquids with a viscosity of 2,680 centistokes (millimeters squared per second) or greater at 20 °C (68 °F), including liquefied compressed gases and refrigerated liquids.

For more material-specific filling limitations, refer to both the T Codes and TP Codes referenced for the material in Column 7 of the § 172.101 Hazardous Materials Table (HMT; § 172.101), and, §§ 173.313, 173.315, 178.276, and 178.277, for liquefied compressed gases and refrigerated liquids in portable tanks.

I hope this information is helpful.  If you have any more questions, please do not hesitate to contact this office.


Robert Benedict
Chief, Standards Development
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.32 Requirements for the use of portable tanks